Soil that allows surface water to seep away into the subsoil not quickly or immediately, but within an hour's time and does not puddle.
‘Red Rocks’ is another hybrid cultivar, named for the Denver, Colorado red sandstone area and amphitheater. P. 'Red Rocks' is highly suitable for the average garden, rather than a specialized penstemon bed. Again, do not deadhead unless reblooming has occurred and you desire a tidier appearance. Don’t over water or over amend the soil, but it will thrive companionably with other medium water-use plants.
Most notable in the meadows and fields of California, the California poppy grows throughout the southwest. Considered to be both annual and perennial, it either comes back the next year or it reseeds. Once you have a stand established, it should continue in your landscape, but not invasively so. This past summer of 2012, my California poppies bloomed in both the spring and our unusual fall. Blooms in April and May. Finely cut blue-green foliage make an attract plant outside the bloom period. The foliage should die back in summer.
It is so refreshing to see the rain lilies bloom after a long hot summer. Whenever they begin to bloom, I know the worst heat is over. Rain lilies are a delightful flower that sends up glossy green, grass-like leaves from its bulb in late spring. In mid to late summer, pure white flowers resembling a crocus open and continue through September, usually after a good summer rainfall. There are quite a few species and varieties (of various colors) of Zephrantes, however, Z. candida is the only rain lily cold hardy in Amarillo. I've grown it successfully since 2008.
Showy evening primrose is a plains states native, including the Texas Panhandle. Showy evening primrose blooms whitish pink in late spring, with each flower lasting a single day, opening in the morning and closing later in the day. The leaves are green narrow and lance-like and emerge from spreading rhizomes. The plant spreads prolifically by rhizomes and seeds, especially in amended and well watered soil. It is not well mannered in a mixed bed or border, I consider it invasive for the garden.
A long-lived evergreen penstemon for the average bed or border. Small orange red tubular flowers attract hummingbirds, as do most red tubular flowers. Low growing and longer flowering than most, especially the more mature the specimen.
After several years, the pine needle like foliage can resemble a miniature bonsai. Pineleaf penstemon is also a must-have for the low water-use bed or border or rock garden because of its evergreen foliage and longer blooming nature. In late summer, snip off the dried, spent flower heads; some re-blooming may occur.
Rarely does a shrub feature as much versatility as the blue mist spirea. It will grow and flower in sun or shade, low water-use or high. This Caryopteris, a hybrid itself, normally blooms in a pleasant light blue, but other selections have deeper blues hues. Summer blooming into fall. And as unlikely at it seems for hybrid to set viable seed, blue mist spirea reproduces itself pleasantly, never invasively. Indeed, any little volunteers are welcome.
Blue grama grass is a short, clumping warm season grass with thin blue green blades that is native throughout the Great Plains and Southwest. Able to grow in poor, dry soils, blue grama grass needs only about 12 inches of annual precipitation to survive. If seeded thick enough and with moderate irrigation, blue grama will form turf. Once establish, reduce to monthly supplemental irrigation, and mow not more frequently than monthly to a height of 4 inches. One advantage of blue grama over buffalograss is the speed of germination; it will germinate in 5-7 days.
Grayleaf cotoneaster is a wonderful low growing shrub for the xeric garden. Evergreen or semi-evergreen in colder winters, it provides good winter interest, along with the other seasons. Small oval shaped silver/gray leaves cover the many arching branches. Tiny white flowers appear in late spring followed by red berries in late fall and winter. Low water use once established.
‘Mersea Yellow’ is similar to the orange red pineleaf penstemon in culture, except for requiring a bit more water. Native perennial to the Southwest. Its leaves are lighter green, but still evergreen, without the tinge of mahogany in winter. ‘Mersea Yellow’ is an excellent selection for the medium water-use zones of your landscape. One of the few yellow flowering penstemons.
Another tough and pretty wildflower that populates a wide area from the plains of Oklahoma down to the Chihuahua Desert and over to Colorado and Utah. Leaves are lower near the base of the plant from which stems emerge and bloom in late spring to early summer. Yellow rays with a red to brownish center.
Curl leaf mountain mahogany is a medium height evergreen shrub native to elevations between 5000-10,000 feet throughout the Southwest. Small oval shaped dark green leaves lightly curl under at the margins are evergreen and aromatic. Small yellow flowers in spring time that develop into grain size fruits with a feathery tail attached to one end (similar to other mountain mahoganies). Slow growing and long lived, it can reach a height of 20 feet or more, but is more typically 6-12 feet. Densely branched. Cold hardy, drought and heat tolerant.
Daffodils are the most notable of the spring bulbs. Reliable from year to year, daffodils can be depended upon to bloom even when faced with late season blizzards and are unpalatable to deer and squirrels. Daffodils aren't too particular about soil, but do better in amended soil, planted about 4 inches deep in October to December. Typical bloom times are February through April, depending on the variety, and there are thousands of varieties to choose from.
This variety of cinquefoil has grown in my xeristrip for six years and flowers happily from late spring into fall, with moderate flowering during the heat of the summer. Will put on a new show of flowers after summer rain. It maintains a compact shape without pruning or any maintenance.
There are many other varieties of this wonderful North American native that grows throughout the Rocky Mountains. Other varieties require moderate watering. This variety was purchased from High Country Gardens; I have not seen this truly drought tolerant variety again.
Texas red yucca is technically not a yucca, but has many of the same qualities as yuccas. Thick, succulent dark olive green leaves grow out of the base, as it is stemless. The coral red flowers appear at the top of a long raceme, often 4-6 feet tall. 'Yellow' and 'Red' blooming yuccas are also available. Although it's natural range is north eastern Mexico and West Texas, it is cold hardy throughout much of the Southwest. Allow for sharp drainage in moister climates to prevent root rot.
Yaupon holly is a tall shrub or a small tree growing typically to 8-12 feet in the Texas Panhandle. Cold hardy to Zone 7 (still best to plant in a protected location), it prefers partial shade, especially afternoon shade. Low (once established) to high water use. Small leathery, glossy, evergreen, dark green leaves (to 1.5” long) have toothed margins on dense branching. Insignificant greenish white flowers in springtime followed by red berries in the fall. Female plants require a male plant to pollinate and bear fruit (dioecious). Attractive tall, traditional looking shrub.
Mat daisy is a low growing spring blooming plant. Drought tolerant. Not exactly a groundcover, as the top growth disappears during summer and reemerges as a green basal rosette in fall, getting ready to bloom again in the spring. Blooms late March to May with small white daisy-like flowers that have pink undersides. Forms a compact ground-hugging mat. Will self seed some, but never invasively.